/*
 * @(#)img_fsutil.h	1.10 06/10/10
 *
 * Copyright  1990-2008 Sun Microsystems, Inc. All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 only, as published by the Free Software Foundation. 
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License version 2 for more details (a copy is
 * included at /legal/license.txt). 
 * 
 * You should have received a copy of the GNU General Public License
 * version 2 along with this work; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA 
 * 
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
 * Clara, CA 95054 or visit www.sun.com if you need additional
 * information or have any questions. 
 *
 */

/*
 * This file contains utility macros used by the Floyd-Steinberg
 * algorithms used in some of the other include files.
 */

#ifndef IMG_FSUTIL_H
#define IMG_FSUTIL_H

#define DitherDist(ep, e1, e2, e3, ec, c)		\
    do {						\
	e3 = (ec << 1);					\
	e1 = e3 + ec;					\
	e2 = e3 + e1;					\
	e3 += e2;					\
							\
	ep[0].c += e1 >>= 4;				\
	ep[1].c += e2 >>= 4;				\
	ep[2].c += e3 >>= 4;				\
	ec -= e1 + e2 + e3;				\
    } while (0)

#endif /* IMG_FSUTIL_H */
